(1) Field of the Invention
This invention relates to a delivery device and a method of delivering a substance to at least one location, more particularly the invention relates to a delivery device comprising one or more capsules within an outer capsule, with at least two of said capsules containing the same active principle and a method of delivering that active principle.
(2) Description of the Related Art
Capsule technology has been developing for over one hundred years and is now at the stage where many medicaments are formulated so as to be encapsulated within a gelatin capsule. The benefits of such formulations reside in the fact that the capsules are often easy for a patient or other consumer to swallow or use and the capsule can contain a large amount of the particular medicament for delivery to the individual, the actual capsule dissolving in the stomach or other part of the intestinal tract.
Indeed, to ensure that a particular medicament is delivered to the desired site, a large amount of research has been carried out in coating techniques. Such techniques are used to control or at least vary the time or location of dissolution of the capsule and, consequently, the time or location of release of the medicament.
Several known techniques have been developed for the administration of more than one active principle at a time or at short intervals whilst the active principle is in tablet form. In those cases, coatings are also used to vary or control the release time or location of that active principle.
U.S. Pat. No. 1,815,902 (Ellzey) discloses a double capsule, with one capsule within the other, for administering medicaments in which an inner hard gel capsule contains medicament, whilst an outer hard gel capsule contains an innocuous alkaline material.
FR 1454013 (Pluripharm) relates to another type of double capsule with different medicaments, in solid form, in the inner and outer capsules which are made of hard gel, whilst DE 2729068 (Liedtke) is directed to a double capsule in which the same or different active principles in solid form are provided in inner and outer hard gel capsules, with any liquids being provided solely in inner and outer soft gel capsules.
In FR 2524311 (Azalbert), there is described another double capsule for the ingestion of medicinal agents which are different and incompatible with one another. The inner and outer capsules are of hard gel, with the medicinal agents possibly being in liquid form.
EP 0116311 (Morishita Jintan Co et al) teaches a double soft gel capsule with the inner and outer capsules containing different medicines, whilst EP 0130163 (Pharmacia) discloses a double capsule with the inner capsule containing an allergen and the outer capsule containing an antiallergie substance.
U.S. Pat. No. 5,310,555 (Zimmer) is directed to a method of delivering incompatible and different compounds in vivo, with live intestinal or rumen microorganisms in an inner capsule and a nutritional supplement in an outer shell in which the inner capsule is contained.
EP 0624365 (ASTA Medica) describes a form of double capsule arrangement in which an outer sheath has bioadhesive properties and contains a capsule containing at least one hygroscopic substance and non-liquid active agent tablets.
WO 95/10262 (RP Scherer Corporation) relates to a controlled release device for delivering a liquid substance to a patient, wherein different materials are contained in a double capsule. The liquid substance is contained in an inner soft or hard gel capsule and an inert solid excipient is contained in an outer hard gel capsule, with a water-swellable material in the outer capsule for causing disengagement of the capsules upon exposure to an aqueous medium.
WO 99/30693, AXCAN PHARMA shows that it is possible to provide a double capsule for the administration of active medicaments in multiple therapies. This disclosure considers the possibility of treating a microorganism, such as Helicobacter pylori, with known solid medicaments in a double capsule.
The multiple capsule delivery devices discussed above show that is known to provide double, triple and, sometimes, quadruple therapies for the treatment of many conditions, wherein the inner and outer capsules can be provided in certain, but not all, combinations of solid and soft get capsules containing the same or different active principles in solid or liquid form.
However, none of the prior art delivery devices discussed above ever discloses, whether directly or by implication, the use of the same active principle as a fluid, such as liquid or semi-solid, in a particular multiple capsule format for the treatment of a plurality of conditions.
Also, these known multiple capsule delivery devices provide treatment regimes which are limited, as it has been found to be difficult to control and vary the posologies, particularly when solid active principles are employed. Indeed, it is known also that certain active principles are not amenable to patients in solid form and it is well established that the most effective dose of most medicaments occurs when the active principles are in liquid form, for example, as an aqueous solution, suspension, micelle or emulsion.